Transport in plants Flashcards
What is the function of a transport system in plants?
To allow a steady supply of water, sugar and minerals to the cells and the removal of waste products out of the cells
What travels in the xylem?
Water and soluble mineral ions
What travels in the phloem?
Sugar and assimilates
Where are xylem and phloem in young roots?
Vascular bundles are found at the centre of the young root, with the xylem in an X or star shape and the phloem in between the arms.
What is around xylem and phloem in young roots?
It is protected by a special sheath of cells called the endodermis, which helps get water into the xylem tisuse
What is in-between the xylem and phloem and the endodermis in young roots?
A layer of meristem ells called the pericycle
Where are xylem and phloem in the stem?
They are found near the outer edge of the stem. They provide strength and flexibility to withstand bending.
The xylem is found towards the inside and the phloem outside, with a layer of cambium in the middle.
What is the difference between vascular bundles in woody and non woody plants in the stem?
In non woody plants the bundles are separate and discrete
In woody plants the bundles are separate in young stems, but become a continuous ring in older stems
What does the cambium do in the stem?
It produces new xylem and phloem cells
Where are xylem and phloem in the leaf?
They form the midrib and veins of a leaf.
What is the outer layer of a stem called?
Collenchyma
What is the second most outer layer of a stem called?
Schlerenchyma
What is the middle part of a stem called?
Medulla
